WO2021241256A1 - Dispositif de traitement au plasma - Google Patents

Dispositif de traitement au plasma Download PDF

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Publication number
WO2021241256A1
WO2021241256A1 PCT/JP2021/018298 JP2021018298W WO2021241256A1 WO 2021241256 A1 WO2021241256 A1 WO 2021241256A1 JP 2021018298 W JP2021018298 W JP 2021018298W WO 2021241256 A1 WO2021241256 A1 WO 2021241256A1
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WIPO (PCT)
Prior art keywords
top wall
plasma processing
frequency
processing apparatus
coaxial line
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PCT/JP2021/018298
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English (en)
Japanese (ja)
Inventor
俊彦 岩尾
貴彰 加藤
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東京エレクトロン株式会社
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Publication of WO2021241256A1 publication Critical patent/WO2021241256A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32082—Radio frequency generated discharge
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32082—Radio frequency generated discharge
    • H01J37/32174—Circuits specially adapted for controlling the RF discharge
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32082—Radio frequency generated discharge
    • H01J37/321—Radio frequency generated discharge the radio frequency energy being inductively coupled to the plasma
    • H01J37/3211—Antennas, e.g. particular shapes of coils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32082—Radio frequency generated discharge
    • H01J37/321—Radio frequency generated discharge the radio frequency energy being inductively coupled to the plasma
    • H01J37/32119—Windows
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32082—Radio frequency generated discharge
    • H01J37/32137—Radio frequency generated discharge controlling of the discharge by modulation of energy
    • H01J37/32155—Frequency modulation
    • H01J37/32165—Plural frequencies
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32431—Constructional details of the reactor
    • H01J37/32623—Mechanical discharge control means

Definitions

  • This disclosure relates to a plasma processing apparatus.
  • Patent Document 1 is a plasma processing apparatus that applies a predetermined plasma treatment to a substrate W to be processed, and the upper electrode is provided with an electrode plate so as to face the lower electrode.
  • the electrode plate has an outer portion made of a conductor or a semiconductor, and a central portion made of a dielectric member or a high resistance member having a higher resistance than the outer portion. This suppresses non-uniformity of the electric field on the electrode surface when high frequency power is applied to the upper electrode.
  • the present disclosure provides a plasma processing apparatus capable of blocking the propagation of high-order modes of electromagnetic waves in the VHF band of 100 MHz or higher and generating uniform plasma.
  • a plasma processing apparatus that supplies electromagnetic waves in the VHF band of 100 MHz or more into a chamber to generate plasma and process the object to be processed, wherein a part of the chamber is used. It has a top wall that is defined and has a ground potential, and a center conductor that is installed in a hole provided in the center of the top wall via a dielectric window and applies the electromagnetic wave. The center position is provided at a position substantially coincide with the center position of the mounting table on which the object to be processed is placed, and the cutoff frequency of the coaxial line composed of the center conductor and the top wall is the frequency of the electromagnetic wave.
  • a plasma processing apparatus in which the outer diameter of the center conductor and the size of the hole in the top wall are defined so as to be larger than the above.
  • FIG. 5 is an enlarged view of the coaxial line length of FIG. 5 up to 100 mm. It is a figure for demonstrating the cutoff frequency.
  • FIG. 10 is an enlarged view of the coaxial line length of FIG. 10 up to 100 mm.
  • FIG. 1 is a schematic cross-sectional view showing a plasma processing apparatus 100 according to a reference example.
  • FIG. 2 is a diagram showing an example of the film thickness distribution at the time of film formation according to the reference example.
  • the plasma processing apparatus 100 includes a chamber 10, a mounting table 12, an upper electrode 14, a coaxial waveguide 20, and a VHF power supply 30.
  • the chamber 10 has a cylindrical shape and extends along the vertical direction.
  • the central axis of the chamber 10 is the axis AX extending in the vertical direction.
  • the mounting table 12 is provided in the chamber 10 on which the substrate W, which is an example of the object to be processed, is mounted.
  • An exhaust port 10e is formed at the bottom of the chamber 10 below the mounting table 12. The inside of the chamber 10 is evacuated through the exhaust space Ex by the exhaust device connected to the exhaust port 10e.
  • an upper electrode 14 is provided via a plasma processing space (hereinafter referred to as a space SP) in the chamber 10.
  • the upper electrode 14 has a disk shape and has a central conductor 14a and a dielectric window 21.
  • the mounting table 12 and the upper electrode 14 face each other, and plasma is generated in the space SP between the mounting table 12 and the upper electrode 14.
  • the plasma processing apparatus 100 has a coaxial waveguide 20 (waveguide r) for supplying electromagnetic waves to the space SP.
  • the coaxial waveguide 20 is composed of a central conductor 14a, a top wall 24, and an upper side wall 10a of a chamber 10 connected to the top wall 24.
  • the coaxial line 201 of the coaxial waveguide 20 is a portion that introduces an electromagnetic wave such as a VHF wave into the space SP as shown in the waveguide r.
  • the top wall 24 and the upper side wall 10a of the chamber 10 define a part of the chamber 10 and have a ground potential.
  • the central conductor 14a constitutes the inner conductor of the coaxial waveguide 20.
  • the top wall 24 and the upper side wall 10a of the chamber 10 form an outer conductor of the coaxial waveguide 20.
  • the coaxial waveguide 20 functions in the same manner as the coaxial cable.
  • the dielectric window 21 is an annular member provided at the tip of the coaxial line 201, and is capable of transmitting electromagnetic waves.
  • the lower surface of the dielectric window 21 is exposed to the space SP, and the electromagnetic wave transmitted through the dielectric window 21 is radiated to the space SP.
  • a VHF power supply 30 is electrically connected via a matching unit 32.
  • the VHF power supply 30 is a power supply that generates electromagnetic waves in the VHF band.
  • the matching unit 32 includes a matching circuit for matching the load-side impedance seen from the VHF power supply 30 with the output impedance of the VHF power supply 30.
  • electromagnetic waves in the frequency band of 100 MHz or higher tend to propagate differently than high frequencies in the lower frequency band.
  • a high frequency of 60 MHz or less is applied, a discharge phenomenon occurs between the upper electrode 14 and the mounting table 12 based on Paschen's law, and plasma based on the processing gas is generated in the space SP.
  • an electromagnetic wave of 100 MHz or more is applied to the upper electrode 14, the electromagnetic wave propagates so as to crawl on the surface (lower surface) of the upper electrode 14, and the processing gas is turned into plasma in the vicinity of the surface of the upper electrode 14. Is generated.
  • FIG. 2 shows an example of the film thickness distribution when a film is formed on a wafer having a diameter of 300 mm as an example of the substrate by the plasma processing apparatus 100 according to the reference example.
  • silane gas (SiH 4 ), ammonia gas (NH 3 ) and helium gas (He) were used as gases, and the pressure in the chamber was controlled to 600 mTorr (about 80 Pa). Further, an electromagnetic wave in the VHF band having a frequency of 220 MHz and a power of 2700 W was applied to form an insulating film.
  • the film thickness distribution is one index of the plasma distribution.
  • the non-uniformity of plasma distribution is considered to be due to the mode of electromagnetic waves.
  • the electromagnetic wave When an electromagnetic wave is radiated from the coaxial line 201 into the space SP, the electromagnetic wave includes a higher-order mode as well as a reference mode. It is considered that the surface wave plasma generated by the electromagnetic wave of this higher order mode has non-uniformity, which causes non-uniformity of the film quality.
  • an electromagnetic wave having a frequency of 100 MHz or higher is propagated on the coaxial line 201, an electromagnetic wave in a high-order mode is generated, causing variation in the film quality.
  • the coaxial waveguide 20 capable of blocking the propagation of electromagnetic waves in the higher-order mode.
  • the TEM mode of electromagnetic waves is a reference mode.
  • the TE11 mode of electromagnetic waves is the mode having the lowest order among the higher order modes. Therefore, if the propagation of the electromagnetic wave in the TE11 mode can be blocked, the propagation of the electromagnetic wave in all the higher-order modes having a higher order can be blocked. Therefore, in the present embodiment, the coaxial waveguide 20 is designed to a size that can block the propagation of the TE11 mode.
  • the plasma processing apparatus 1 which has the coaxial waveguide 20 designed to have a size capable of blocking the propagation of the TE11 mode, will be described.
  • FIG. 3 is a schematic cross-sectional view showing the plasma processing apparatus 1 according to the embodiment.
  • the plasma processing apparatus 1 has a chamber 10, a mounting table 12, an upper electrode 14, a coaxial waveguide 20, and a VHF power supply 30.
  • the chamber 10 has a cylindrical shape and extends along the vertical direction.
  • the central axis of the chamber 10 is the axis AX extending in the vertical direction.
  • the chamber 10 is made of a conductor such as aluminum or an aluminum alloy.
  • a corrosion-resistant film is formed on the surface of the chamber 10.
  • the corrosion resistant film is a ceramic such as aluminum oxide or yttrium oxide.
  • the mounting table 12 is provided in the chamber 10.
  • the mounting table 12 is configured to support the substrate W mounted on the upper surface thereof substantially horizontally.
  • the mounting table 12 has a disk shape.
  • the central axis of the mounting table 12 substantially coincides with the axis AX.
  • An exhaust port 10e is formed at the bottom of the chamber 10 below the mounting table 12.
  • An exhaust device is connected to the exhaust port 10e.
  • the exhaust system includes a pressure control valve and a vacuum pump such as a turbo molecular pump and / or a dry pump.
  • the inside of the chamber 10 is evacuated by the exhaust device through the exhaust space Ex.
  • the upper electrode 14 is provided above the mounting table 12 via the space SP in the chamber 10.
  • the upper electrode 14 has a disk shape.
  • the mounting table 12 and the upper electrode 14 face each other, and surface wave plasma is generated in the space SP between the mounting table 12 and the upper electrode 14.
  • the surface wave plasma is generated near the surface of the upper electrode 14.
  • the plasma processing device 1 has a coaxial waveguide 20 (waveguide r) for supplying an electromagnetic wave to the space SP.
  • the coaxial waveguide 20 is composed of a central conductor 14a and a top wall 24, and introduces an electromagnetic wave of VHF wave of 100 MHz or more from the coaxial line 201 to the space SP.
  • the central conductor 14a constitutes the inner conductor of the coaxial waveguide 20.
  • the top wall 24 constitutes the outer conductor of the coaxial waveguide 20.
  • the coaxial waveguide 20 composed of the central conductor 14a and the top wall 24 has the same function as the coaxial cable.
  • the central axis of the top wall 24 and the center conductor 14a substantially coincides with the axis AX.
  • the term "substantial match” includes the case where the match is not perfect due to the mechanical processing accuracy.
  • the through hole formed in the center of the top wall 24 is expanded inside the top wall 24 to form a step portion 24a, whereby the center conductor 14a is arranged in the space extending to the outer peripheral side in the top wall 24. That is, the central conductor 14a is provided in a space that penetrates the through hole at the center of the top wall 24 and extends toward the outer periphery inside the top wall 24.
  • the top wall 24 defines a part of the chamber 10 and has a ground potential.
  • the central conductor 14a may be made of a metal such as aluminum or may be made of another conductor material.
  • the central conductor 14a has a shaft portion 14a1 and a diameter-expanded portion 14a2 that extends radially from the shaft portion 14a1 at the lower portion of the shaft portion 14a1.
  • the shaft portion 14a1 has a columnar shape, and the diameter-expanded portion 14a2 has a disk shape.
  • the central conductor 14a has a T-shaped vertical cross section.
  • An electromagnet 35 is embedded in the top wall 24 so as to form an annular shape as a whole, and the electron density of the plasma can be maintained high by confining the electrons in the plasma in the magnetic flux of the electromagnet 35. This makes it possible to adjust the distribution of plasma.
  • the electromagnet 35 may be provided on at least one of the top wall 24 and the side wall 10a of the chamber 10. However, the electromagnet 35 may not be provided.
  • the dielectric window 21 formed in the coaxial waveguide 20 is located at least at the tip of the coaxial line 201 and has a first solid dielectric layer 21a that separates the inside of the coaxial line 201 from the plasma space.
  • the dielectric window 21 is composed of a first solid dielectric layer 21a, and the first solid dielectric layer 21a is located between the outer peripheral end portion of the enlarged diameter portion 14a2 and the inner side wall 24b of the top wall 24. It is provided in.
  • the thickness of the first solid dielectric layer 21a is substantially equal to the thickness L of the enlarged diameter portion 14a2. That is, the first solid dielectric layer 21a is embedded in the entire coaxial line 201 which will be treated as a coaxial line in the calculation described later.
  • the first solid dielectric layer 21a is capable of transmitting electromagnetic waves. The lower surface of the first solid dielectric layer 21a is exposed to the space SP, and the electromagnetic wave transmitted through the first solid dielectric layer 21a is radiated to the space SP.
  • a VHF power supply 30 is electrically connected above the upper electrode 14 via a matching unit 32.
  • the VHF power supply 30 is a power supply that generates electromagnetic waves in the VHF band.
  • the VHF power supply 30 outputs an electromagnetic wave in the VHF band of 100 MHz or more.
  • the matching unit 32 includes a matching circuit for matching the load-side impedance seen from the VHF power supply 30 with the output impedance of the VHF power supply 30.
  • the electromagnetic wave propagates from the VHF power supply 30 to the dielectric window 21 in the coaxial line 201, passes through the dielectric window 21, and is supplied to the space SP from the lower surface of the dielectric window 21.
  • the electromagnetic wave used is a VHF wave of 100 MHz or more and 300 MHz or less.
  • Gas pipes are formed on the top wall 24 and the central conductor 14a.
  • a gas supply source is connected to the gas pipe.
  • the gas supply source supplies one or more gases used for processing the substrate W.
  • the gas supply source includes one or more flow rate controllers for controlling the flow rate of one or more gases.
  • the gas supplied into the pipes of the top wall 24 and the central conductor 14a is discharged to the space SP through a plurality of gas discharge holes opened in the space SP.
  • the gas is excited by the electric field of the surface wave of the electromagnetic wave formed in the space SP, and plasma (surface wave plasma) is generated from the gas.
  • plasma surface wave plasma
  • the substrate W on the mounting table 12 is treated with a chemical species from the plasma.
  • the mounting table 12 may be provided with a conductive layer for an electrostatic chuck and a conductive layer for a heater.
  • a DC voltage from a DC power source is applied to the conductive layer for the electrostatic chuck, an electrostatic attractive force is generated between the mounting table 12 and the substrate W.
  • the substrate W is attracted to the mounting table 12 by the generated electrostatic attraction and is held by the mounting table 12.
  • the plasma processing device 1 may further include a baffle member.
  • the baffle member extends between the mounting table 12 and the side wall of the chamber 10.
  • the baffle member is an annular plate material. A plurality of through holes are formed in the baffle member.
  • the plasma processing device 1 may further include a control unit 40.
  • the control unit 40 may be a computer including a processor, a storage unit such as a memory, an input device, a display device, a signal input / output interface, and the like.
  • the control unit 40 controls each unit of the plasma processing device 1.
  • the operator can perform a command input operation or the like in order to manage the plasma processing device 1 by using the input device.
  • the control unit 40 can visualize and display the operating status of the plasma processing device 1 by the display device.
  • a control program and recipe data are stored in the storage unit.
  • the control program is executed by the processor in order to execute various processes in the plasma processing device 1.
  • the processor executes a control program and controls each part of the plasma processing device 1 according to the recipe data.
  • an electromagnetic wave in the VHF band of 100 MHz or higher is applied to the central conductor 14a, and the generated plasma is used to process the substrate W.
  • the size of the coaxial waveguide 20 is designed to be large enough to block the propagation in the TE11 mode.
  • the dimensions of the coaxial waveguide 20 for blocking the propagation of the TE11 mode are defined by the outer diameter of the central conductor 14a and the dimensions of the holes in the top wall 24.
  • the cutoff frequency of the coaxial line 201 composed of the central conductor 14a and the top wall 24 is set to be at least twice the frequency of the electromagnetic wave in the VHF band of 100 MHz or more applied in the chamber 10.
  • the outer diameter of the center conductor 14a and the dimensions of the holes in the top wall 24 are specified.
  • the results of a simulation performed to optimize the outer diameter of the center conductor 14a and the dimensions of the holes in the top wall 24 to the size for blocking the TE11 mode will be described.
  • the dimension of the outer diameter of the central conductor 14a is the diameter d of the enlarged diameter portion 14a2
  • the dimension of the hole of the top wall 24 is the dimension of the top wall 24 facing the outer peripheral side wall of the enlarged diameter portion 14a2.
  • the length of the coaxial line 201 (coaxial line length L) shown in FIG. 3 is equal to the thickness of the enlarged diameter portion 14a2.
  • FIG. 4 is a table showing the relationship between the outer diameter of the central conductor 14a, the size of the hole in the top wall 24, and the cutoff frequency according to the embodiment.
  • 4 (a) is the ratio between the outer diameter of the center conductor 14a when the dielectric constant epsilon r was used 9.7 alumina to the first solid dielectric layer 21a (the diameter d of the enlarged diameter portion 14a2) top wall 24
  • the relationship between the hole (diameter D of the inner side wall 24b of the top wall) and the cutoff frequency is shown.
  • the diameter d of the enlarged diameter portion 14a2 is shown as an inner diameter d [mm]
  • the diameter D of the inner side wall 24b of the top wall is shown as an outer diameter D [mm].
  • the coaxial waveguide 20 of the above size when an electromagnetic wave having a frequency f smaller than 438 MHz is applied from the VHF power supply 30, the propagation of the electromagnetic wave in the higher order mode can be suppressed. It is possible to sufficiently attenuate the higher-order mode of the electromagnetic wave having a frequency f smaller than 219 MHz, which satisfies the condition of f ⁇ fc / 2 in which the safety factor is doubled.
  • FIG. 5 is a diagram showing an example of cutoff frequency and electromagnetic wave attenuation according to one embodiment.
  • the horizontal axis represents the distance x of the coaxial line from the port excited by the electromagnetic field in the line direction, and the vertical axis represents the complex amplitude
  • Higher-order mode electromagnetic waves are sufficiently attenuated.
  • the electric fields of electromagnetic waves having a frequency of f1 (43.8 MHz) and a frequency of f2 (219 MHz) are monotonically reduced in the coaxial waveguide 20 and are sufficiently attenuated.
  • the electromagnetic wave in the high-order mode having a frequency f larger than 438 MHz, which satisfies the condition of f> fc is not attenuated and propagates in the coaxial waveguide 20.
  • FIG. 6 is an enlarged view of the coaxial line length L of FIG. 5 up to 100 mm.
  • the alternate long and short dash line S indicates a half value of the electric field of the excited electromagnetic wave.
  • the coaxial line length L in order to attenuate the electric field of the electromagnetic wave having the frequency f1 (43.8 MHz) and the frequency f2 (219 MHz) to the electric field indicated by the alternate long and short dash line S, the coaxial line length L must be at least 20 mm. Recognize.
  • the electric fields of electromagnetic waves having a frequency of f3 (394 MHz) and a frequency of f4 (433 MHz) are monotonically reduced and attenuated in the coaxial waveguide 20.
  • the attenuation per unit distance is smaller than that of electromagnetic waves having frequencies f1 and f2.
  • the attenuation of the electric field of the electromagnetic wave having a frequency of f5 (438 MHz) is even smaller.
  • the coaxial line length L needs to be at least 30 mm.
  • the frequency f4 (433 MHz) it is necessary to further increase the coaxial line length L.
  • the inner diameter D may be specified. This can also largely attenuate the propagation of high-order modes of electromagnetic waves in the VHF band of 100 MHz or higher.
  • FIG. 7 is a diagram for explaining the cutoff frequency fc. As shown in FIG. 7, assuming that the outer diameter of the inner conductor of the coaxial waveguide is d and the inner diameter of the outer conductor is D, the cutoff frequency fc is calculated by the equation (1).
  • c is the speed of light (3 ⁇ 10 8 [m / s]), is epsilon r is the relative permittivity of the dielectric.
  • the frame shown by A in FIG. 4A is a range showing a cutoff frequency fc that is more than twice the electromagnetic wave having a frequency of 200 MHz, which is a simulation condition. If the outer diameter d of the center conductor 14a and the inner diameter D of the hole in the top wall 24 are specified so as to have a size having a cutoff frequency fc in the A frame, the TE11 mode and others when an electromagnetic wave having a frequency of 200 MHz is applied. High-order mode electromagnetic waves can be sufficiently attenuated. This makes it possible to generate a uniform plasma.
  • the frame shown by B in FIG. 4A is a range showing a cutoff frequency fc smaller than an electromagnetic wave having a frequency of 200 MHz, which is a simulation condition. If the outer diameter d of the center conductor 14a and the inner diameter D of the hole in the top wall 24 are specified so as to have a size having a cutoff frequency fc in the B frame, the TE11 mode and other modes are used when an electromagnetic wave having a frequency of 200 MHz is applied. Electromagnetic waves in higher-order mode propagate and cannot be blocked.
  • the coaxial line length L is specified to be at least 20 mm as shown in FIG. If the coaxial line length L is specified to be 40 mm, the higher-order mode can be sufficiently attenuated. Further, if the outer diameter d of the center conductor 14a and the inner diameter D of the hole of the top wall 24 are specified so as to have a size having a cutoff frequency fc not included in the A frame and the B frame, the condition of fc> f ⁇ fc / 2 is satisfied. The electromagnetic wave in the higher-order mode having a frequency f satisfying the condition is attenuated. However, the amount of attenuation is smaller than the amount of attenuation of electromagnetic waves in the higher-order mode having a frequency f satisfying the condition of f ⁇ fc / 2 in the A frame.
  • the surface wave of the electromagnetic wave propagating through the upper electrode 14 is used. It is possible to generate a more uniform electric field distribution and generate a uniform plasma not only in the circumferential direction but also in the radial direction. Further, the electron density of the plasma can be controlled by confining the electrons in the plasma in the magnetic flux of the electromagnet 35.
  • FIG. 4B shows the relationship between the dimensions of the coaxial waveguide 20 and the cutoff frequency when an air layer in a vacuum space having a relative permittivity ⁇ r is used for the coaxial line 201.
  • FIGS. 8A and 8B are diagrams showing an example of the upper electrode 14 of the plasma processing apparatus 1 according to the modified example of the embodiment.
  • the first solid dielectric layer 21a may be used for a part of the coaxial line 201, and the air layer 21b may be provided for another part.
  • the thickness of the first solid dielectric layer 21a is thinner than the thickness of the enlarged diameter portion 14a2.
  • the frequency of the air layer 21b is 200 MHz as shown in the A frame of FIG. 4 (b) with respect to the portion of the air layer 21b.
  • the range showing a cutoff frequency fc that is more than twice that of electromagnetic waves is widened.
  • first solid dielectric layer 21a at the tip of the coaxial line 201 so as to be a partition from the plasma space and prevent plasma from entering the coaxial line 201.
  • the thickness of the first solid dielectric layer 21a may be 1/4 or less with respect to the coaxial line length L.
  • the thickness of the first solid dielectric layer 21a may be 5 mm or more from the viewpoint of mechanical strength.
  • the dielectric window 21 has a first solid dielectric layer 21a in a part of the dielectric window 21, and a second solid dielectric layer having a lower relative permittivity than the first solid dielectric layer 21a in the other part. You may have.
  • the first solid dielectric layer 21a may be, for example , any substance of alumina (Al 2 O 3 ), aluminum nitride (AlN), and quartz.
  • the first solid dielectric layer 21a may be a substance having a lower relative permittivity than these alumina, aluminum nitride and quartz.
  • the second solid dielectric layer is a substance having a lower relative permittivity than the first solid dielectric layer 21a.
  • FIG. 9 is a diagram showing the relationship between the dimensions of the coaxial waveguide 20 and the cutoff frequency fc according to the embodiment.
  • the cutoff frequency fc of the coaxial waveguide 20 having an inner diameter d of 140 mm and an outer diameter D of 160 mm is 204 MHz shown in the C frame.
  • the coaxial waveguide 20 having the above size can sufficiently attenuate the electromagnetic wave in the higher-order mode having a frequency f smaller than 102 MHz, which satisfies the condition of f ⁇ fc / 2.
  • the electromagnetic wave in the higher-order mode having a condition of f> fc that is, a frequency f larger than 204 MHz, is not attenuated and propagates.
  • FIG. 10 is a diagram showing an example of cutoff frequency and electromagnetic wave attenuation according to an embodiment.
  • the horizontal axis represents the distance x of the coaxial line from the port excited by the electromagnetic field in the line direction, and the vertical axis represents the complex amplitude
  • the electric fields of electromagnetic waves having a frequency of f9 (20.4 MHz) and a frequency of f10 (102 MHz) are monotonically reduced in the coaxial waveguide 20 and are sufficiently attenuated.
  • the electromagnetic wave in the high-order mode having a frequency f larger than 204 MHz, which satisfies the condition of f> fc is not attenuated and propagates.
  • electromagnetic waves having a frequency f14 (206 MHz), a frequency f15 (224 MHz), and a frequency f16 (408 MHz) do not monotonically decrease in the coaxial waveguide 20, but propagate in the coaxial waveguide 20.
  • FIG. 11 is an enlarged view of the coaxial line length L of FIG. 10 up to 100 mm, and shows the coaxial line length L required for the electric field of the excited electromagnetic wave to be attenuated by half.
  • the alternate long and short dash line S indicates a half value of the electric field of the excited electromagnetic wave.
  • the coaxial line length L needs to be at least 35 mm. You can see that.
  • the electromagnetic wave in the high-order mode having a frequency f larger than 102 MHz and smaller than 204 MHz, which is shown in FIG. 10, is attenuated, but is less attenuated than the electromagnetic wave in the high-order mode having a frequency f of 102 MHz or less.
  • the electric fields of electromagnetic waves having a frequency of f11 (183 MHz) and a frequency of f12 (201 MHz) are monotonically reduced and attenuated in the coaxial waveguide 20.
  • the attenuation is less than that of electromagnetic waves having frequencies f9 and f10.
  • the attenuation of the electric field of the electromagnetic wave having a frequency of f13 (204 MHz) is even smaller.
  • the center conductor 14a serves as an internal conductor and the top wall 24 serves as an external conductor. Any configuration may be used as long as it functions as a cable.
  • FIG. 8B is a diagram showing an upper electrode 14 of the plasma processing device 1 according to another modification of one embodiment.
  • the upper electrode 14 is provided at the through hole of the top wall 24.
  • the through hole of the top wall 24 is the inner side wall 24b of the top wall 24 and corresponds to the hole of the top wall 24.
  • the central conductor 14a is only the shaft portion 14a1 and does not have a diameter-expanded portion.
  • the vertical cross-sectional shape of the central conductor 14a is I-shaped.
  • the outer diameter d of the central conductor 14a is the diameter of the shaft portion 14a1, and the size of the hole in the top wall 24 is the inner diameter D of the inner side wall 24b of the top wall 24.
  • the dielectric window 21 is composed of a first solid dielectric layer 21a and an air layer 21b in a vacuum space having a lower relative permittivity than the first solid dielectric layer 21a.
  • the coaxial line length L is the thickness of the top wall 24.
  • the thickness of the first solid dielectric layer 21a is thinner than the coaxial line length L.
  • the cutoff frequency fc of the coaxial line 201 composed of the central conductor 14a and the top wall 24 is outside the central conductor 14a so as to be larger than the frequency of the electromagnetic wave in the VHF band of 100 MHz or more to be applied.
  • the diameter d and the inner diameter D of the inner side wall 24b of the top wall 24 are defined.
  • the outer diameter d of the central conductor 14a and the inner side wall of the top wall 24 are set so that the cutoff frequency fc of the coaxial line 201 is at least twice the frequency of the electromagnetic wave in the VHF band of 100 MHz or more to be applied. It is more preferable that the inner diameter D of 24b is specified.
  • the plasma processing apparatus 1 of the present embodiment it is possible to block the propagation of high-order mode electromagnetic waves of electromagnetic waves in the VHF band of 100 MHz or higher and generate uniform plasma. Further, by reducing the diameter of the upper electrode 14, it is possible to achieve uniformity of plasma not only in the circumferential direction but also in the radial direction.
  • the electromagnet 35 By providing the electromagnet 35 on the top wall 24 or the side wall 10a, the electron density in the plasma is controlled by confining the electrons in the plasma in the magnetic flux of the electromagnet 35, so that the uniformity of the plasma can be further improved.
  • the plasma processing apparatus according to the embodiment disclosed this time is exemplary in all respects and is not restrictive.
  • the above embodiment can be modified and improved in various forms without departing from the scope of the attached claims and the gist thereof.
  • the matters described in the plurality of embodiments may have other configurations within a consistent range, and may be combined within a consistent range.
  • the plasma processing device 1 is not limited to a film forming device as long as it is a device that performs a predetermined treatment on a substrate using plasma, and may be an etching device, an ashing device, or the like.
  • Plasma processing device 10 Chamber 12 Mounting table 14 Upper electrode 14a Center conductor 14a 1 Shaft 14a2 Expanded diameter 20 Coaxial waveguide 21 Dielectric window 21a First solid dielectric layer 21b Air layer 24 Top wall 24b Internal side wall of top wall 30 VHF power supply 35 Electromagnet 40 Control unit 201 Coaxial line W board

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Plasma Technology (AREA)

Abstract

L'invention concerne un dispositif de traitement au plasma qui fournit des ondes électromagnétiques dans une bande VHF de pas moins de 100 MHz dans une chambre et qui génère un plasma de façon à traiter une cible de traitement. Le dispositif de traitement au plasma présente une paroi supérieure qui définit une partie de la chambre et qui comporte un potentiel de masse, et un conducteur central qui est installé dans un trou dans le centre de la paroi supérieure par l'intermédiaire d'une fenêtre diélectrique et sur lequel des ondes électromagnétiques sont appliquées. La position centrale du conducteur central correspond sensiblement à la position centrale d'une base de placement sur laquelle la cible de traitement est placée, et la fréquence de coupure d'une ligne coaxiale constituée par le conducteur central et la paroi supérieure est définie par le diamètre extérieur du conducteur central et par les dimensions du trou dans la paroi supérieure de manière à être supérieure à la fréquence des ondes électromagnétiques.
PCT/JP2021/018298 2020-05-26 2021-05-13 Dispositif de traitement au plasma WO2021241256A1 (fr)

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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0368771A (ja) * 1989-08-04 1991-03-25 Canon Inc マイクロ波プラズマ処理装置
JPH09106900A (ja) * 1995-05-19 1997-04-22 Hitachi Ltd プラズマ処理方法及びプラズマ処理装置
JPH11260594A (ja) * 1998-03-12 1999-09-24 Hitachi Ltd プラズマ処理装置
JP2002237483A (ja) * 2001-02-07 2002-08-23 Hitachi Ltd プラズマ処理装置
JP2003163204A (ja) * 2001-11-28 2003-06-06 Hitachi Ltd プラズマ処理装置
JP2006324551A (ja) * 2005-05-20 2006-11-30 Shibaura Mechatronics Corp プラズマ発生装置及びプラズマ処理装置
JP2019110047A (ja) * 2017-12-19 2019-07-04 株式会社日立ハイテクノロジーズ プラズマ処理装置
WO2020066843A1 (fr) * 2018-09-26 2020-04-02 東京エレクトロン株式会社 Dispositif de traitement par plasma et procédé de traitement par plasma

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW516113B (en) * 1999-04-14 2003-01-01 Hitachi Ltd Plasma processing device and plasma processing method
JP4454718B2 (ja) 1999-05-07 2010-04-21 東京エレクトロン株式会社 プラズマ処理装置およびそれに用いられる電極
JP4572100B2 (ja) * 2004-09-28 2010-10-27 日本エー・エス・エム株式会社 プラズマ処理装置
US20100078315A1 (en) * 2008-09-26 2010-04-01 Applied Materials, Inc. Microstrip antenna assisted ipvd
US9971970B1 (en) * 2015-04-27 2018-05-15 Rigetti & Co, Inc. Microwave integrated quantum circuits with VIAS and methods for making the same
JP6960737B2 (ja) * 2017-01-23 2021-11-05 株式会社日立ハイテク 真空処理装置
US10923324B2 (en) * 2017-07-10 2021-02-16 Verity Instruments, Inc. Microwave plasma source

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0368771A (ja) * 1989-08-04 1991-03-25 Canon Inc マイクロ波プラズマ処理装置
JPH09106900A (ja) * 1995-05-19 1997-04-22 Hitachi Ltd プラズマ処理方法及びプラズマ処理装置
JPH11260594A (ja) * 1998-03-12 1999-09-24 Hitachi Ltd プラズマ処理装置
JP2002237483A (ja) * 2001-02-07 2002-08-23 Hitachi Ltd プラズマ処理装置
JP2003163204A (ja) * 2001-11-28 2003-06-06 Hitachi Ltd プラズマ処理装置
JP2006324551A (ja) * 2005-05-20 2006-11-30 Shibaura Mechatronics Corp プラズマ発生装置及びプラズマ処理装置
JP2019110047A (ja) * 2017-12-19 2019-07-04 株式会社日立ハイテクノロジーズ プラズマ処理装置
WO2020066843A1 (fr) * 2018-09-26 2020-04-02 東京エレクトロン株式会社 Dispositif de traitement par plasma et procédé de traitement par plasma

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